Effect of cattle manure application on pod yield and yield indices of okra (Abelmoschus esculentus L. Moench) in a semi-arid sub-tropical environment

The effects of cattle manure rate and time of application on okra yield and yield indices were studied at Harare, Zimbabwe during two cropping seasons (2000-2002). The treatments were factorial combinations of four cattle manure rates (0, 6, 12 and 18 t ha -1 ) and two application timings (4 and 8 weeks after planting). The experiment was a randomized complete block design with four replications. Both cumulative green pod count and yield were increased by manure application up to 12 t ha -1 in 2000 and 6 t ha -1 in 2001. Yield values for the best manure rates were 131 and 123% of those for the control in 2000 and 2001 respectively. Average green pod weight and length were increased by manure application in one year only (2000). Application of manure 6 t ha -1 gave the highest dry pod weight while 12 t ha -1 produced the highest weight of seeds pod -1 . Parameters were generally not influenced by time of manure application or rate x timing interaction. Leaf Ca was slightly higher for earlier applied manure and for 6 and 12 t ha -1 than for no manure or 18 t ha -1 . Pod N was also slightly higher for earlier manure application than for the later application. The best manure rate would vary with manure quality. However, application of manure 6 t ha -1 as early as possible in the cropping season appears to be best for okra production in semi-arid Zimbabwe.